A polyol is a raw material compound of polyurethanes, polyesters or the like. Among the polyols, since the polyester polyols have excellent physical properties, they have been used as elastomer parts of a raw material for manufacturing a roll for a printing device, a belt for conveyance, a blade for a copying machine; a raw material of urethane fibers or the like.
As the polyester polyol-related technology, Patent Document 1 discloses a composition obtained by adding 0.05 to 1000 ppm of phosphorus compound such as a trialkyl phosphate or the like to a polyester polyol. Patent Document 2 discloses a method for producing a polyester polyol including adding water to a polyester polyol which is produced using a titanium-based catalyst and heating, followed by adding a phosphorus compound having a specific structure to the resulting mixture in an amount such that the amount of phosphorus atoms is 0.01 to 2 mol with respect to 1 mol of titanium atoms. Patent Document 3 discloses a method for producing an ester-based polymeric polyol composition in which a urethanization reaction is restrained including adding a phosphorus compound having a specific structure to an ester-based polymeric polyol produced using a titanium-based esterification catalyst in an amount such that the amount of phosphorus atoms is 1 mol with respect to 1 mol of titanium atoms.
Patent Document 4 discloses that a polyester is produced by reacting an aliphatic dibasic acid with an aliphatic di(alcohol) in an aromatic compound solvent in the presence of a protic strong acid catalyst such as phosphoric acid. In this process, the used amount of the protic strong acid catalyst is preferably 0.01 to 5% by weight of the reactants.
Patent Document 5 discloses a method for preparing a copolymer from at least one cyclic monomer selected from among: a lactone, lactam, carbonate, or lactide, and from among a glyclolide, oxazoline, epoxide, or cyclosiloxane in the presence of a phophorous-substituted compound such as diphenyl phosphate, (R)-3,3′-bis[3,5-bis(trifluoromethyl)phenyl]-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate or the like. The phosphorus-substituted compound is used in an amount of 1 to 3 mol with respect to 1 mol of a hydroxyl group or thiol group in a polymerization initiator such as 3-phenyl-1-propanol, n-pentanol or the like.
Furthermore, Non-Patent Document 1 discloses a polyester polyol produced by ring-opening polymerization of ε-caprolactone or δ-valerolactone using 1 mol of diphenyl phosphorate catalyst with respect to 1 mol of a polymerization initiator such as 3-phenyl-1-propanol or the like.